炼厂罐区废气治理装置远程监控系统设计

介绍了以工控机、PLC以及控制设备和检测仪表所组成的炼油厂罐区油气回收自动监控系统。工控机通过组态王软件进行组态,PLC作为现场控制单元,配合各种检测设备对油气回收装置中的工艺参数进行采集,实时监测废气处理过程与设备运行状态,并对现场调节阀和动设备进行相应控制。同时,利用现场总线进行数据交换,完成整套装置的自动监控与管理。从监控结果中可知,PLC与上位机之间数据传送可靠稳定、操作简单,提高了炼油厂的监控和管理水平。     

基于Host Link协议的PLC监控软件设计

以VB6.0为平台,设计了上位机对PLC的监控软件。上位机与PLC之间的通信基于欧姆龙(OMRON)内嵌FINS命令的HostLink协议。利用VB的ActiveX控件MSComm实现了PLC与上位机之间的串行通信。上位机通过对PLC的读/写,实现了对现场数据的采集、存储和配方操作。实验表明,利用此监控软件可以有效地对工业现场设备进行监控和管理。     

基于CITECT组态软件和PLC的高纯度干冰生产过程监控系统

针对高纯度千冰生产过程的复杂性,研究一种基于CITECT组态软件和PLC的集散控制系统,整个监控系统由上位计算机、二台现场控制器PLC、通讯模块和现场执行单元构成,对干冰的生产过程进行全程控制和管理.上位计算机使用CITECT组态软件设计各种监控画面,并通过监控画面对PLC进行参数设置,接收参数后的PLC完成系统监视、诊断和控制任务.上位计算机与现场PLC之间采用SYSMAC WAY协议进行通信.该系统配置灵活,可靠性高.通过工程实际应用表明,本文实现的控制系统能有效地解决高纯度干冰生产过程这类复杂工业对象的过程控制问题.     

PLC在PBT输送监控系统中的应用

针对PBT输送工艺的特点和控制要求,采用下位机PLC对现场设备进行智能控制,组态王作为上位机组态软件,对现场设备监督与管理,高可靠性的HMI确保操作员站操作正确、方便.     

基于工业组态软件WinCC的化工工业监控系统

介绍一种应用于化工厂的动态计算机监控系统,该系统以上位机的西门子WinCC5.1和下位机的西门子S7-300系列PLC为核心进行动态监视与控制.详细论述了监控系统中上位机软件的设计与实现,以及人机界面动画的制作,介绍了上位机与下位机PLC的通讯方式.概述了丁酯合成与回收系统的结构和特点.     

油库自动售油系统中PLC的应用研究

本文主要就油库自动售油系统中PLC的实际应用进行简单讨论,该自动化系统主要工作核心为计算机系统,以实现对现场的控制以及实时的监视。同时,本文还将该系统结构进行了简单的剖析,对功能进行介绍,与此同时,还对如何信号采集以及数据信息的处理以及PLC与上位机之间如何通信进行简单的介绍以及分析。     

基于PLC和WinCC的化工精馏塔控制系统设计

化工精馏塔控制系统以SIEMENS公司的S7-300 PLC作为数据采集及控制单元,配合各种检测和控制设备时温度、压力、流量等检测量进行数据采集,在PLC程序中用PID对检测量进行调整.上位机通过西门子的上位监控软件WinCC和PLC进行数据交换,从而实现集中控制.     

基于MCGS和PLC的草甘膦膜分离控制系统设计

设计构造了一个控制草甘膦膜分离的组态系统。该系统采用工业控制计算机作为上位机,下位机采用PLC,同时使用数据采集板卡和智能模块,将工控机与PLC二者优点结合,同时配合增压泵、切断阀、变频器在生产中使用。在MCGS组态环境中,开发草甘膦膜分离控制界面,对整个系统进行自动控制。     

煤矿压风设备三维可视化实时监控预警系统的实现

煤矿压风设备三维可视化实时监控及预警系统运用三维可视化虚拟仿真技术与PLC控制技术相结合对现场设备进行实时三维监控的半实物仿真系统。采煤现场各种设备的实时数据通过传感器采集后传输给PLC系统,PLC系统通过专用接口将数据传给上位机,再运用OPC技术将现场采集的数据实时存储进实时数据库中,最后,三维仿真模块根据数据库中的实时数据来控制虚拟环境中的各种设备进行动作。以Visual C＋＋和Eon作为开发工具,采用适合煤矿实体建模及应用的三维数据模型和数据结构,并采用几何建模、三维交互以及颜色、光照和材质等虚拟现实技术,开发煤矿三维可视化实时监控系统。     

基于S7-300 PLC与WINCC的锅炉液位控制系统

系统设计以西门子公司的S7-300PLC作为数据采集及控制单元,配合各种检测和控制设备对锅炉液位进行控制。上位机通过西门子的上位机监控软件WinCC和各站进行数据交换,从而实现集中控制。     

Insect antifeedant properties of anthranoids from the genusVismia

Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.     

2007～2008年世界塑料工业进展

收集了2007年7月～2008年6月世界塑料工业的相关资料,介绍了2007～2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.     

2005～2006年国外塑料工业进展

收集了2005年7月～2006年6月国外塑料工业的相关资料,介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。按通用热塑性树脂（聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂）、工程塑料（聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚）、通用热固性树脂（酚醛、聚氨酯、不饱和树脂、环氧树脂）、特种工程塑料（聚苯硫醚、液晶聚合物、聚醚醚酮）的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。